Polymorphic analysis of hypervariable mimisatellite related to recombination hot spot

人类串联重复序列约占人类基因组的3%，并且（不包括卫星DNA）根据重复单元的大小和重复阵列的总长度分为两组。人类小卫星或可变数目串联重复（VNTR）基因座具有6bp至超过100bp长的重复单元，这取决于基因座，其中阵列的长度通常为100bp。人类富含GC的小卫星优先聚集在染色体的重组有效亚端粒区域。一些小卫星基因座表现出非常高的等位基因长度变异性，大多数小卫星基因座由两个或更多个细微不同的重复单元类型（小卫星变异重复）的异质阵列组成。迄今为止表征的所有人类高变小卫星不仅在重复拷贝数（等位基因长度）上变化，而且在阵列内这些变体重复单元的散布模式上变化。这种内部变化提供了一个强大的方法， ...更多信息 等位基因变异研究及突变处理。小卫星变异重复序列（MVR）定位可以确定散布模式，揭示了比等位基因长度分析更大的变异性。等位基因大小分布表明，日本人保留广泛的等位基因长度变异，但有显着较小的等位基因相比，北欧人。通过MVR-PCR进一步表征了92个日本等位基因。这些等位基因表现出多种多样的内部MVR结构，大多数等位基因在样品中仅观察到一次。真实杂合性估计为99.95%，在日本人群中存在2000个不同的等位基因表达良好。点阵分析表明，共享结构基序的相关等位基因组可以在日本人和北欧人中识别，并且这些组是人群特异性的，没有任何日本人和北欧等位基因之间的显着相似性的例子。因此，小卫星B6.7在日本和北欧人群中表现出巨大的等位基因变异和快速的重复更新，为探索人类历史上最近的事件提供了新的谱系标记，我们还分析了日本人群中另一个高变小卫星CEB 1（D2S90）的特性。长度杂合度为85.0%，等位基因平均长度为69个重复。在小卫星侧翼发现了一个新的单核苷酸多态性（SMP）。等位基因间的内部MVR结构不同，重复序列中发现了新的Vase替换/缺失，这表明CEB1也是日本人最高变的小卫星位点之一。少

Human tandem repeats account for about 3% of the human genome and (excluding satellite DNA) are classified into two groups according to the size of the repeat unit and the overall length of the repeat array. Human minisatellites or variable number tandem repeat (VNTR) loci have repeat units from 6 bp to more than 100 bp long depending on the locus, with arrays usually kilobases in length. Human GC-rich minisatellites are preferentially found clustered in the recombination-proficient subtelomeric regions of chromosomes. Some minisatellite loci show very high levels of allele length variability.Most minisatellite loci consist of heterogeneous arrays of two or more subtly different repeat unit types (minisatellite variant repeats). All human hypervariable minisatellites characterized to date vary not only in repeat copy number (allele length) but also in the interspersion pattern of these variant repeat units within the array. This internal variation provides a powerful approach to the st … More udy of allelic variation and processed of mutation. Interspersion patterns can be determined by minisatellite variant repeat (MVR) mapping and reveals far more variability than can be resolved by allele length analysis.We analyse minisatellite B6,7 locus in the Japanese population. Allele size distributions showed that Japanese retain extensive allele length variability but have significantly smaller alleles compared to north Europeans. Ninety-two Japanese alleles were further characterised by MVR-PCR. These alleles showed a wide variety of internal MVR structures with most alleles observed only once in the sample. The true heterozygosity is estimated at 99.95%, with well in express of 2000 different alleles existing in the Japanese population. Dot matrix analysis showed that groups of related alleles sharing structural motifs could be identified within Japanese and in north Europeans, and that these groups are population-specific with no examples of significant similarity between any Japanese and north European alleles. Minisatellite B6.7 therefore shows huge allele variability and fast repeat turnover in Japanese as well as north European populations, and provide novel lineage markers for exploring very recent events in human population history.We also anlaysed the properties of another hypervariable minisatellite CEB1 (D2S90) in the Japanese population. The length heterozygosity is observed at 85.0% and the average length of the alleles is 69 repeats. A new single nucleotide polymorphism (SMP) was found in the flanking the minisatellite. Internal MVR structure was different between alleles and new vase substitutions/deletions were found within repeats, which indicates CEB1 is also one of the most hypervariable minisatellite loci in Japanese. Less